This invention relates to an axial flow combine in which crop material is fed into a cylindrical foraminous cage through a radial feeder opening at one of its axial ends where it is threshed by a rotor having rasp bars. As threshing occurs, the crop material is moved by helical bars on the inside of the cage to a radial discharge opening adjacent the other axial end of the cage.
U.S. Pat. No. 4,108,150 issued on Aug. 22, 1978 to J. L. Shaver on an Agitator for an Axial Flow Cylinder shows a foraminous cage which has radial threshing openings in the cylindrical cage wall except for the feeder opening and the discharge opening. Material passing through small radial openings in the cage above the feeder opening and gravitating downwardly fell into a trough and an auger conveyed the material inward to a central point where it was discharged and fell to distribution augers and, thence, to accelerator rolls. The provision of an overfeed auger and its drive train adds to the initial cost of the combine and requires the usual service and maintenance to keep it in a good operating condition.
In one combine of the before-mentioned type, the perforated cage sections above the feeder opening were replaced by cylindrical nonperforated sections. These nonperforated sections were the width of the feeder opening and extended from the top of the feeder opening to the top of the horizontally disposed cylindrical cage. Also, the cylindrical trough and the overfeed auger were eliminated with a resulting vertical opening between the cage and the processor housing directly above the feeder conveyor. Since the cage was not perforated above the feeder opening, crop material did not pass through that part of the cage and threshing capacity was reduced. The air turbulence within the processor housing caused a substantial quantity of separated crop material to pass downwardly through the vertical opening onto the feeder conveyor, thus causing undesirable recycling of some separated crop material.